Layer 2 Networks
Understand Layer 2 networks, how they scale a base blockchain, and the main execution, settlement, bridge and sequencing risks.
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A Layer 2 (L2) moves some work away from the base chain while relying on that base layer for important security, settlement or data-availability functions.
The L2 model
On Ethereum, the dominant L2 approach is the rollup: transactions execute away from Mainnet, are batched, and information needed to validate the result is posted back to Ethereum. This spreads base-layer costs across many users.
Submitted to the L2.
Transactions are ordered and executed on the L2.
Many transactions are compressed together.
Data and/or proofs are posted to the base chain.
Why L2s exist
Keeping every transaction on a decentralised base layer can be expensive during high demand. L2s aim to preserve much of the base layer’s security while lowering cost and increasing throughput.
| Dimension | L1 | L2 |
|---|---|---|
| Execution | On base chain | Mostly off the base chain |
| Transaction cost | Usually higher under congestion | Usually lower due to batching |
| Settlement | Native | Ultimately anchored to L1 for rollups |
| Extra operational components | Fewer layers | Sequencers, bridges, proof systems and upgrade controls may matter |
Key L2 risks
How to assess an L2
- Where is transaction data stored?
- What proof or dispute mechanism validates state transitions?
- Can users exit if the sequencer is unavailable?
- Who can upgrade contracts or pause the system?
- How mature is the bridge and how much value depends on it?
- What is the gap between “soft” confirmation and L1 settlement/finality?
Quick checkpoint
- What problem is this mechanism trying to solve?
- Where does execution happen and where does settlement or finality come from?
- Which new operational, bridge, sequencing or consensus risks appear?
Common misunderstandings
- Cheaper does not automatically mean safer. Lower fees can come with different trust, bridge, sequencer or validator assumptions.
- “Scaling” is not one technology. L1 upgrades, L2 rollups and sidechains solve throughput constraints in different ways.
- Token price and network quality are separate questions. A technically strong network can still have poor token economics, and the reverse can also be true.
FAQ
Is every fast Ethereum-compatible chain an L2?
No. Some are independent sidechains. A useful distinction is whether the system derives security and settlement from Ethereum and posts the required data or proofs to it.
Do L2 transactions become final instantly?
Not necessarily. Users may see a fast local confirmation, while stronger settlement depends on the rollup design and eventual L1 inclusion/finality.
Why do L2s often have their own tokens?
Tokens may be used for governance, incentives or other functions, but an L2 does not technically require a token simply to exist.
Summary
The useful question is not simply whether a network is “fast”. Compare execution, settlement, data availability, consensus, bridge design and operational maturity. Those layers determine how a scaling system behaves when conditions are normal — and when something goes wrong.
Last reviewed: 20 August 2026
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